Speed governor for internal-combustion engines



, Jufiy 17, T1923- v HA-fil933 E R. PIERCE SPEED GOVERNOR FOR INTERNAL coMBus'rIbN mamas ML I Filed oct. 51. 1919 2 sheets sheet 1 X? Q Q awuwtoq July 1'3, 1923- Filed Oct. 31. 1919 2 Sheets-Sheet 2 8mm [30622) fierce attozwu areas an v, reaa Y n aanrn rinaonornocnnsrnn, MICHIGAN, nssrcitoa 'ro 'monancn cor nation" oorrrnnr, or nnrnorrmrcnrosn, a oonronarron or. rrrcrirean.

srnnneovnanonron INTERNAL-COMBUSTION ENGINES.

a neauon'm a was a1, 1919. .Serial' no. seams.

To' all whom it may concern:

Be it known that l, E RALPH PmRon,. a citizen of'the United States of America, residing at Rochester, in the county of Oak- 5 land and State of Michigan, have invented certain new and useful Improvements in Speed Governors for. Internal-Combustion Engines, of which the following is a specification, reference being had therein, to the m accompanyin drawing. a

The invention relates to governors for in.- ternal combustion engines of that type in which the admission -of the combustible chargeis controlled by slight variations in 15 speed to prevent further variation. It is the object of the invention; first, to obtain more sensitive means of response to variations second, to simplify the construction.

For various uses it is desirable togovern internal combustion engines so as to maintain a substantially constant maximumspeed or a predetermined limit of speed under varying conditions of load. In one type of governor this is accomplished by Q5 mechanical means driven by a .moving part which adj usts the throttle, or other controlling means, for the combustible mlxture. In

, another type an adjustment is accomplished by the variable pressure of gases passing W through the intake. With both types there is required a counter-acting'force, such as a spr1ng, or its been experienced in securing a proper reaction. This is for the reason that the curve 5 representing the reactionof an ordinary spring differs the variable forcederived from the engine and it is therefore difiicult to obtain the balancing of force'required for corrective adto justment of the throttle.

It isone of the features of my 1m roved construction that the force employed, or adjusting the throttle is the var able static within the intake. Another feature is the t5 peculiar characteristic of the'reactive force. and the method of obtaining the same, as.

hereinafter set forth.

In the drawin Figure 1 is a to section through one form of my improve governor Figures 2 and'3 are similar v ews of modified constructions; I

Figure 4: is a diagram illustrating the iagrammatic longitudinal to the variable equivalent,'but difiiculty has.

from the curve representing lines, respectively tangent to difi'erent tension method of deriving a spring, or other reactive force, corres nding in characteristic orce derived from the en ine.

y improved governor is applicable either to engines controlled by a throttle, or to those in which the control is over the. fuel alone and not the combustible mixture. 1' .have, however, specifically shown and will describe this applicationto the former type only. With this type foreach variation in load there must be a corresponding 'adjust ment of the throttle if the speed or R. P. M.

is maintained'substantially constant. Also for each adjustment of the throttle, the load varying and the R. P. M. remaining constant, therewill bee definite condition of pressure within the intake. Making use of the latter-fact, my improved governor o erates upon the principle of adjusting the throttle by variations in the static pressure within the intake in cooperation with a properly. compensated springor other op-- 'posingforce.

g The ethod of deriving the proper adjust- V ment 0? opposed -force is as follows: The

engine is operated under varying loads and with each variation the throttle is adjusted until a predetermined constant maximum speed is obtained. Also with each adjustment, the static pressureiwithin the intake is accurately measured. A curve is then plotted in variables of throttle opening and intake pressure to determine the proper characteristic of the re-active force required.

This curve, as represented b the line A--B in Figure 4, has a ver di erent characteristic from the curve 0 an ordinary spring, which latter is a substantially straight line as, for instance, represented bythe line A-C in Figure 4. However, a series of straight I- tions of the curve A--B, will if oombi ed have substantially the same characteristic said curve,'and each of these straight lin s' is representative of a .particular spring or group of springs. Thus, as shown, the ins 'A-O, which is tangent to aportion of the curve A--B, represents a spring of certain another portion of said curve, represents a spring, or a group of springs, of a different the line Tit-E, which is tangent to a succeeding portion of the curve, repred tension; the line C-D, which is tangent to sents still another spring or group of springs, and so on. To produce a spring having the characteristic of the curve A-C, D-E, etc., a series of simple springs may be compounded, so that their combined effect will correspond to the curve. Thus, in each positionvof adjustment the reaction of the spring will correspond to the force derived from the intake, producing a state of equilibrium.

The construction illustrated in Figure 1 is one form of my invention, in which G is V a cylinder containing a piston H which is connected bythe pitman rod I with the rock-arm J for adjusting the throttle. K is a conduit'leading from the end of the cylinder G to the engine intake K, by which the pressure within said cylinder is equalized with the static pressure within the intake. L, L, L are the several units of a compound spring, each of which is selected to produce, in cooperation with the other units, the desired characteristic. These springs, as shown, are arranged in tandem and surround the rod I, each element having its action limited by a suitable stop, such as formed by the thimbles M, M, etc. One end of the spring abuts against the cylinder G, while the opposite end isin engagement with a collaron the rod I, such as the nut N.

In operation, whenever there is a change in load upon the engine, this will produce a change in static pressure Within the intake, which is communicated to the cylinder G. This in turn will unbalance the pressures upon opposite sides of the piston H, one side of which is exposed to atmospheric pressure, and the differential pressure assistmg or opposing the compoundspring will cause an adjustment of the piston, which through the rod I operates the rock-arm J and adjusts the throttle. Furthermore, the several elements of the spring will operate successively, the action being-limited by the stop thimbles M, M, etc., thereby producing just the required movement of the throttle for each change-of load to maintain the R. P. M. constant. I 1

In the modified constructions shown in Figures 2 and 3 the same principle is emploigedin a more compact structure. Thus in igure 2, O is a collapsible sealed chamber of bellows form, which is arranged .within the casing P, forming a portion of the intake. One end of this chamber is attached to a valve Q for engaging a seat Q, and which forms the governing throttle, while the other end of the chamber is anchored'to a suitable spider R. A compound spring S, similar in construction to that shown in Figure 1, is arranged within a portion P of the casing to operatively engage the valve Q. With this construction the operation is substantially the same, the. static pressure the pressure of the air sealed within the chamber 0, or in communication with the external atmosphere, is substantially constant.

In theconstruction shown in Figure 3, the arrangement is substantially the same as in Figure 2, With the exception that the chamber O has arranged therewithin the easing 0' within which is located the compound spring S.

In each of the several modifications, variations in static pressure incident to a change of load on the engine will unbalance the opposing forces resulting in adjustment of the throttle, or other engine controlling means, so as to maintain with the changed load a substantially constant speed.

a What I claim as my invention is-- 1. A governor for internal combustion engines comprising a controlling member subjected to variable pressure corresponding to variations in static pressure in the intake incident to changes in the load, a plurality of springs arranged in tandem form-, ing an opposing pressure upon said member,

and thimbles separating said springs, each of said springs being of different tension.

governor for internal combustion engines comprising a controlling member subjected to variable pressure corresponding to variations in static pressure in the intake incident to changes in the load, a plurality of springs of different tension arranged in tandem to form an opposing pressure upon said member, and means for limiting the.

action of each of said springs to a predetermined range whereby said controlling member is actuated to maintain a substantially constant speed of the engine under changing loads.

3. A governor for internal combustion engines comprising a controlling member subjected to-variable pressurecorresponding to thevariations in static pressure in the intake incident to changes'in load, a plurality of springs arranged to form an opposing pressure upon said member, and means for limiting the action of each of said springs to a predetermined range whereby the combined action of said springs corresponds to a'predetermined characteristic.

4.. A governor for internal combustion engines comprising a controlling member subected to variable pressures incident to variations inoperating the engine, a plurality of springs arranged to form an opposing pressure upon said member, and means for limiting the action of one of said springs whereby the combined action of said springs corresponds to a predetermined characteristic such as to maintain under changing loads a substantially constant speed.

5. In a governor for internal combustion engines the combination with a throttle valve controlling the fuel supply to the intake, of a member for actuating said throttle subjected to variable pressure corresponding to the static pressure in said engine, a plu- 5 rality of springs arranged to form an opposing pressure upon said member, and means for limiting the action of each of said springs to a predetermined range whereby the combined action of said springs has a characteristic such as to maintain sub stantially constant speed under varying conditions of load.

In testimony whereof I afiix my signature.

E RALPH PIERCE. 

